Functionalized alpha-olefin copolymers having narrow molecular weight distribution

Claim 2

A functionalised elastomeric polymer having a molecular weight distribution less than 2.0 and comprising up to 5 milliequivalents per 100 grams of the polymer of at least one functionality selected from the group consisting of: -C(O)OH, -C(H₂)OH and -NH(R₁) wherein R₁ may be hydrogen or a hydrocarbon radical containing from 1 to 20 carbon atoms.

Claim 3

The elastomeric polymer of claim 1 wherein said polymer is a segmented A-B or A-B-A polymer and wherein substantially all of said functionality occurs within at least one A segment constituting 30 to 50 wt% of said polymer.

Claim 4

The elastomeric polymer of claim 2 wherein said polymer is a segmented A-B polymer and substantially all of said functionality occurs within the A segment, said A segment constituting up to 50 wt% of said polymer.

Claim 5

The elastomeric polymer of any preceding claim comprising copolymerised ethylene and at least one alpha-olefin.

Claim 6

The elastomeric polymer of claim 4 wherein said alpha-olefin comprises propylene.

Claim 7

The elastomeric polymer of claim 4 or 5 additionally comprising a diene monomer.

Claim 8

The elastomeric polymer of claim 6 wherein said diene monomer is 1, 4-hexa-diene, 5-ethylidene-2-norbornene, or dicyclopentadiene.

Claim 9

The elastomeric polymer of any preceding claim which contains from 1 to 3 milliequivalents per 100g of the polymer, of said at least one functionality.

Claim 10

The elastomer polymer of any of claims 4 to 8 which comprises from 15 to 85 wt% of ethylene.

Claim 11

A process for the preparation of a functionalised elastomeric polymer according to any one of the preceding claims, comprising:- A) providing masked, unsaturated functional monomers, obtainable by chemically reacting unsaturated functional monomers with non-halogenated organometallic compounds; B) copolymerising in a Ziegler-Natta polymerisation reaction conducted in a mix-free reactor such that essentially all polymer chains are initiated substantially simultaneously, the masked, unsaturated functional monomer and at least two other monomers preferably ethylene and at least one alpha-olefin; and C) de-ashing the reaction product of step B) to form the desired polymer having incorporated therein functional polymer units derived from the masked, functional monomer.

Claim 12

The process of claim 10 in which one of said other monomers comprises a diene monomer, wherein the diene monomer is copolymerised in step B).

Claim 13

A process according to claim 10 or 11 in which the copolymerisation step B) is performed: (a) in at least one mix-free reactor system in which substantially no mixing occurs between portions of the reaction mixture that contain polymer chains initiated at different times, (b) with essentially one active catalyst species, (c) using at least one reaction mixture which is essentially transfer agent-free, and which further comprises: (d) conducting the copolymerisation in a manner and under conditions sufficient to initiate propagation of essentially all copolymer chains simultaneously, the copolymer chains produced being dispersed within the reaction mixture.

Claim 14

A process according to claim 12 wherein step (d) comprises: (i) forming the active catalyst species by pre-mixing catalyst components and aging the pressurised catalyst components for at least 0.1 second, and (ii) intimately mixing the active catalyst species with solvent and monomers such that the copolymer chains produced are dispersed within the reaction mixture.